BRANCHBURG, N.J. — President Trump signaled Sunday that he does not believe that attempts at direct communications with North Korea are worth the effort despite escalating tensions between Washington and Pyongyang.

A day after Secretary of State Rex Tillerson suggested that the United States maintains “lines of communications” with Kim Jong Un's regime, Trump wrote on Twitter that Tillerson is “wasting his time trying to negotiate with Little Rocket Man” — his nickname for Kim.

The president has taken an increasingly hard-line stance toward Pyongyang over its nuclear weapons and ballistic missile tests, threatening  in a speech to the U.N. General Assembly two weeks ago to “totally destroy” North Korea if necessary.

Tillerson, on a visit to Beijing, told reporters Saturday that the State Department is “probing” through direct channels with the North whether Kim would be open to talks and under what conditions.

Secretary of State Rex Tillerson said that the U.S. has multiple direct channels of communication with North Korea during a visit to China. (Reuters)

“We ask, ‘Would you like to talk?’ We have lines of communications to Pyongyang. We’re not in a dark situation, a blackout. We have a couple, three, channels open to Pyongyang; we can talk to them; we do talk to them,” Tillerson  said.

“Stay tuned,” he added.

Trump, who is spending the weekend at his Bedminster golf resort in New Jersey, has said repeatedly that he is open to military options. North Korean officials have suggested that Trump's threats amount to a declaration of war.

Later Sunday, Trump said he would succeed where his predecessors had not, but he noted that U.S. diplomacy with Kim has failed over 25 years. Kim is 33 and only came to power after his father, Kim Jong Il, died in December 2011.

Why does North Korea hate the U.S.? Look to the Korean War. (Anna Fifield, Jason Aldag/The Washington Post)